Compact compressed gas launching device

ABSTRACT

A paintball gun comprised of a simplified firing system that eliminates many of the seals and complexity of a typical gun that uses the bolt as a spool type valve. The gun contains a bolt with a gas chamber around it, one seal inside of it, and one seal on its outside. A cylinder rod inside the bolt pushes the bolt forward against a spring using pressurized gas routed via a pilot valve, moving the bolt into the fire position. In the fire position the rear of the bolt moves off the inner seal, allowing compressed gas stored around the bolt to move into and thru the bolt, firing the paintball. Releasing pressure from behind the cylinder rod allows the spring to push the bolt rearward and seal the gas chamber. The simplified mechanism should be more consistent, allow more shots per tank and require less maintenance than other guns.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Patent application claims priority to Provisional Application #60763430 filed on Jan. 30, 2006

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was not developed under any federal sponsorship, grant, or funding

BACKGROUND OF INVENTION

1. Field of the Invention

The present invention relates to valves used in compressed gas operated launching devises. Including but not limited to devices used for launching gelatin capsules containing paint, commonly referred to as “paintballs”.

2. Related Art

The game of paintball as a form of recreation uses pneumatic guns that launch gelatin capsules containing paint (paintballs). Participants fire these “guns” at each other. Such guns have two basic mechanisms; One for chambering a capsule or “ball” into the breach of the gun, the other to release a burst of gas behind the ball in order to propel it.

A vast number of paintball guns use a valve that is comprised of chambering device or “bolt” that also acts as the valve that releases the gas to fire the ball. These are commonly referred to as “spool valve” style guns. The bolt is moved axially forward to chamber the ball into the breach. At the apex of the motion, once the ball is in the breach, the bolt moves past some form of seal that allows high pressure gas to enter the breach and propel the ball out of the barrel. The bolt is usually moved by means of applying gas pressure to a chamber on the outside of the bolt which then acts against a lip on the bolt's exterior. The main gas pressure chamber is usually behind the bolt or around a rear section of the bolt. While this design provides for a fast actuation and a simple design, it also requires a significant amount of axial length to accommodate the necessary components. Furthermore, the number of seals required for these designs introduces a large amount of friction force. The friction force can vary from shot to shot. This variation can cause variation in how long the bolt is forward and how much gas is released to the ball. To minimize the variations in how much gas is released to the ball, some of these “spool valve” markers incorporate an “on-off” mechanism as part of the bolt. When the bolt is rearward a gas chamber is allowed to fill with gas. When the bolt moves forward it closes the chamber off to any more incoming gas. The chambered gas is what propels the ball when the gun fires. This on-off mechanism necessitates more seals, and hence more complexity to the paintball gun. Finally, the use of an exterior lip on the bolt to propel it forward and rearward usually makes the gas passages from the air chamber to the ball smaller then they might otherwise be. The small passages create the need for higher gas pressures to move the needed gas from the chamber to the ball. These higher pressures tend to wear-out O-rings and further contribute to friction. These higher pressures also make it necessary to use high pressure solenoid valves to actuate the bolt or a secondary pressure regulator to allow use of standard, low pressure solenoid valves. Both situations increase the cost of a paintball launching device.

What would be advantageous is valve that could be used in place of the current spool valves that would be more compact in size and reduce the overall length and complexity of the gun. Said design should not require an on-off mechanism and should operate with the minimum amount of seals. Furthermore it should have large air passages to minimize the pressure needed to operate the marker.

BRIEF SUMMARY OF THE INVENTION

The object of this invention is to provide a ball chambering and valve mechanism for paintball launching devices that has a bolt and valve mechanism combined into a simple and consistent gas powered gun

According to the present invention, a gas powered gun comprises a gun barrel, a cylindrical breach, a cylindrical bolt movable between a loading position in which the end of the bold is withdrawn from the breach to permit a paintball to be fed into the breach through an opening in the side of the breach, and a firing position in which the bolt has moved forward to cause the front of the bolt to engage the paintball and move the paintball forward into the barrel, a trigger operable to cause the bolt to move forward from the loading position to the firing position and a pressurized gas supply

In the load position a paintball would be in the breach. The bolt is comprised of an outer shell, a raised lip on the rear of the outer shell, an inner surface of the shell, a front face with axial holes permitting connecting the front of the bolt to the inside of the shell, and a tappet or rod of a diameter significantly smaller than the inside if the bolt that extends from the front face of the bolt rearward.

The bolt is held rearward in the body of the gun by a compression spring acting against the outside lip of the bolt. Compressed gas is allowed to flow into a compressed gas chamber via a primary compressed gas inlet that brings gas in from the compressed gas supply. The chamber is around outside of the bolt and the inside of the rear of the bolt. The gas is prevented from flowing out of the bolt via a cylinder that protrudes from the rear of the gas chamber into the inside of the bolt. The end of this cylinder contains a main seal that acts on the inside of the bolt to prevent gas from flowing thru the holes in the face of the bolt. The tappet extends inside this protruding cylinder.

To fire a paintball, compressed gas would be routed via a valve from the gas supply to the area directly behind the tappet. The compressed gas would push the tappet and in turn the bolt forward. As the bolt moves forward it would push the paintball into the breach and seal off any other paintballs from being loaded. At the end of the forward stroke of the bolt, the rear of the bolt is no longer in full contact with the main seal, either by means of coming off the seal completely or by means of radial holes a the rear of the bolt. With the bolt off the seal compressed gas from the main chamber can flow rapidly thru the bolt, around the tappet, and thru the gas passages in the face of the bolt. This burst of gas will propel the paintball down and then out of the barrel.

After the paintball is fired the gas pushing the tappet is vented out the secondary inlet and the spring is allowed to push the bolt and tappet rearward. This seals off the main chamber and prevents any more gas from venting, and returns the bolt to the ready-to-fire position.

The gun may also include an adjustable pressure regulator connected between the pressurized gas supply and the first chamber. Furthermore a second pressure regulator could be included between the gas supply and the valve that allows gas to the rear of the piston. Said secondary regulator could also be positioned such that it used gas from the first pressure regulator.

This invention overcomes the shortcomings of the existing art by the following means;

There are only two seals acting on the bolt and one on the tappet, as opposed to as many as six seals in existing designs. The reduction in seals reduces the potential variance in friction and bolt travel times. The position of the tappet down the center of the bolt allows for a compact mechanism both in length and in diameter. The position of the air chamber around the outside and inside of the bolt allows a large air chamber in a small space. The need to compress a spring on the forward stroke of the bolt necessitates a higher amount of force than the dual acting pistons of existing designs by approximately two to one. This higher force needed to move the bolt forward halves the effect of variances in friction on the bolt travel time, and hence the amount of time compressed gas is allowed to flow to the paintball. The position of the main seal inside the bolt and the air chamber outside the bolt allows for passages between the air chamber and the paintball to be wide and short, essential to low pressure operation.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a diagrammatic sectional view of a paintball gun showing the bolt in the loading position

FIG. 2 is a diagrammatic sectional view similar to FIG. 1 that shows the bolt in the firing position

FIG. 3 is a diagrammatic sectional view similar to FIG. 1 that shows the bolt in the about-to-fire position

FIG. 4 is a diagrammatic sectional view close up from FIG. 3 showing the bolt in the about-to-fire position

DETAILED DESCRIPTION OF THE INVENTION

One embodiment of the invention will now be described, by way of example, with references to the accompanying drawings

A paintball gun has a housing 1 with a barrel 2 secured to the front of the housing 1. A hand grip with trigger guard 3 is secured to the bottom of the housing 1, with a trigger 4. Paintballs 5 are fed downwardly into the housing 1 thru a supply passage 6 in a manner known in the art. Pressurized gas such as compressed air, nitrogen, or CO2 would be supply to the pressure regulator 7 from a tank or supply line known in the art. The pressure regulator 7 is attached to the bottom of the housing 1 forward of the hand grip and trigger guard 3. The pressure regulator can be of any style know in the art and will not be shown in detail

The housing 1 contains a main gas passage 20 that allows gas to flow from the outlet of the pressure regulator 7 to the main chamber 9 and the chamber extension 18

The housing 1 contains a bolt 8 which is slidably mounted in the main chamber 9 of the housing 1. The bolt 8 has a front portion that projects into the breach 10 of the housing 1. On the outside of the bolt 8 a sealing ring 11 seals compressed gas in the main chamber 9. A second sealing ring 12 is positioned on the inside of the bolt 8 and is held on the cylinder 13. The outside diameter of the sealing ring 12 and the inside diameter of the sealing ring 11 are the same diameter so that when compressed gas is present in the main chamber 9, the gas does not bias the bolt either forward or rearward.

The bolt 8 has gas passages 14 allowing communication between the inside of the bolt 8 with the front of the bolt 8. A spring 15 is positioned on around the outside of the bolt 8 and bias' the bolt rearward until it stops against the cylinder 13. A tappet 16 is positioned inside the cylinder 13 and is sealed against the cylinder with a seal 17. The tappet 16 extends forward and is presses against the face of the bolt 8.

The cylinder 13 resides in the main chamber 9 and has gas passages 21 thru it allowing communication with the main chamber extension 18. The chamber extension 18 is sealed off in the rear with the rear cap 19.

A valve 22 is contained in the grip frame 3 and is attached to the housing 1. The valve 22 is a solenoid 3-way valve as known in the art. The valve 22 is normal closed to the main chamber 9 and open to the gas passage 25, allowing the space behind the tappet to be in communication with atmospheric pressure. The valve 22 is operable by the trigger 4 and trigger switch 24 mounted on a circuit board 26. When the trigger 24 is pressed, an electrical signal is sent via the circuit board 26 to the valve 22. The valve 22 shifts to the open position causing pressurized gas to be supplied from the main chamber 9 to passage 25. The gas being supplied thru passage 25 acts on the rear of the tappet 16. The tappet 16 pushes against the bolt 8 and propels them both forward. The bolt 8 compresses the spring 15 as it moves forward. The bolt 8 chambers a paintball 26 into the rear of the barrel 2. At the apex of the bolt 8's travel the rear of the bolt 8 moves past the sealing ring 12, allowing compressed gas to flow from the main chamber 9 thru the bolt's gas passages 14 and to the paintball 26. This burst of gas propels the paintball 26 thru the barrel 2, effectively shooting the paintball.

After a fraction of a second determined by the circuit board 26, the valve 22 shifts back to its normally closed position, closing off the main chamber 9 and venting the compressed gas from behind the tapped 16. The spring 15 is then free to push the bolt 8 and tappet 16 rearward. Almost immediately the rear of the bolt 8 re-seals against the sealing ring 12, preventing any more compressed gas from flowing out of the main chamber 9. The bolt 8 and tappet 16 continue rearward until they return fully to the loading position.

The burst of compressed gas released from the main chamber 9 causes the gas pressure in the main chamber 9 to drop and in turn drops the pressure in the main chamber extension 18 and the gas passage 20. The pressure regulator 7 senses the pressure drop in the main chamber 9 via the gas passage 20 and opens flow from a pressurized gas tank or supply line until the gas pressure in the main chamber 9 reaches the pre set limit determined by the pressure regulator 7. The paintball gun has now completed one full cycle. 

1. A gas powered gun comprising: a gun barrel, a cylinder containing a piston slidably movable between a loading position in which the leading edge of the bolt is sufficiently withdrawn to permit a projectile to be fed into the cylinder through an opening in the side thereof, and a firing position in which the piston has moved fowardly to cause the leading edge of the piston to engage the projectile and move the projectile fowardly into the barrel, a trigger operable to cause the piston to move from the loading position to the firing position, a pressurized gas supply, said cylinder having a primary chamber thru which the piston extends, said pressurized gas supply supplying pressurized gas to the chamber, said piston having a longitudinally extending passage extending from the front to the rear of the piston. said chamber containing a tube that extends from the rear of the chamber into the inside of the piston, said chamber containing a seal on the forward end that seals against the outside of the piston preventing gas from the chamber flowing around the outside of the piston to the barrel, said tube containing a seal on its outside that seals against the inside passage of the piston and prevents gas from the primary chamber flowing thru the piston when the piston is in the load position and allows gas to flow thru the piston when the piston is in the fire position,
 2. A gun according to claim 1 wherein the piston is moved forward from the load to the fire position by a the application of the pressurized gas to the rear of a secondary piston that extends axially from the front of the piston rearward thru the piston internal passage toward the rear of the piston and whose end resides inside a cylinder in the tube that extend from the rear of the primary chamber
 3. A gun according to claim 2 wherein said application of the gas supply to secondary piston is achieved via a valve that is operatively connected to the trigger whereby movement of the trigger causes the valve to supply pressurized gas to the rear of the secondary piston via the cylinder in the tube.
 4. A gun according to claim 3 wherein the forward seal of the primary chamber has a sealing diameter equal to the sealing diameter of the seal on the outside of the tube, allowing the piston to have zero net forces imposed on it from the gas in the primary chamber and containing a compression spring coiled around the outside of the piston that acts against the front of the primary chamber and a lip on the outside of the piston, constantly biasing the piston rearward with enough force to move it and keep it rearward when the secondary piston is not being acted upon by pressurized gas, but weak enough that it will compress and allow the piston to move forward when the secondary piston is acted upon by pressurized gas.
 5. A gun according to claim 3 wherein the forward seal of the primary chamber has a sealing diameter less than the sealing diameter of the seal on the outside of the tube, creating a cross section of the piston that the gas in the primary chamber can act upon, pushing it rearward with enough force to move it and keep it rearward when the secondary piston is not being acted upon by pressurized gas, but weak enough that it will allow the piston to move forward when the secondary piston is acted upon by pressurized gas.
 6. A gun according to claim 1 also including a secondary gas chamber located rearward of the primary chamber and rearward of the center tube that is in communication with the primary chamber via gas passages that extend thru the rear of the primary chamber and into the secondary chamber
 7. A gun according to claim 6 also including a pressure regulator connected between the pressurized gas supply and the first chamber
 8. A gun according to claim 7 also including a second pressure regulator connected between the pressurized gas supply and the valve that actuates via the trigger with said second regulator having gas fed from the primary gas chamber, the secondary gas chamber, the first pressure regulator, or directly from the pressurized gas supply
 9. A piston and cylinder assembly for a gas powered gun, said piston assembly comprising: a cylinder containing a piston slidably movable between a loading position in which the leading edge of the piston is sufficiently withdrawn to permit a projectile to be fed into the cylinder through an opening in the side thereof, and a firing position in which the piston has moved fowardly to cause the leading edge of the piston to engage the projectile and move the projectile fowardly into an extended portion of the cylinder, said cylinder having a primary chamber thru which the piston extends, said chamber being pressurized from a pressurized gas supply, said piston having a longitudinally extending passage extending from the front to the rear of the piston. said chamber containing a tube that extends from the rear of the chamber into the inside of the piston, said chamber containing a seal on the forward end that seals against the outside of the piston preventing gas from the primary chamber flowing around the outside of the bolt to the leading edge of the cylinder or the projectile, said tube containing a seal on its outside that seals against the inside passage of the piston and prevents gas from the primary chamber flowing thru the piston when the piston is in the load position and allows gas to flow thru the bolt when the bolt is in the fire position,
 10. A piston and cylinder assembly according to claim 9 wherein the piston is moved forward from the load to the fire position by a the application of the pressurized gas to the rear of a secondary piston that extends axially from the front of the first piston rearward thru the piston's internal passage toward the rear of the piston and whose end resides inside a cylinder in the tube that extend from the rear of the primary chamber
 11. A piston and cylinder assembly according to claim 10 wherein said application of a gas supply to the secondary piston is achieved via a valve that is connected to the primary chamber and said application of the gas supply to the secondary piston causes both pistons to move from the load to the fire position.
 12. A piston and cylinder assembly according to claim 11 wherein the forward seal of the primary chamber has a sealing diameter equal to the sealing diameter of the seal on the outside of the tube, allowing the piston to have zero net forces imposed on it from the gas in the primary chamber and containing a compression spring coiled around the outside of the piston that acts against the front of the primary chamber and a lip on the outside of the piston, constantly biasing the piston rearward with enough force to move it and keep it rearward when the secondary piston is not being acted upon by pressurized gas, but weak enough that it will compress and allow the piston to move forward when the secondary piston is acted upon by pressurized gas.
 13. A piston and cylinder assembly according to claim 11 wherein the forward seal of the primary chamber has a sealing diameter less than the sealing diameter of the seal on the outside of the tube, creating a cross section of the piston that the gas in the primary chamber can act upon, pushing it rearward with enough force to move it and keep it rearward when the secondary piston is not being acted upon by pressurized gas, but weak enough that it will allow the piston to move forward when the secondary piston is acted upon by pressurized gas.
 14. A piston and cylinder assembly according to claim 9 also including a secondary gas chamber located rearward of the primary chamber and rearward of the center tube that is in communication with the primary chamber via gas passages that extend thru the rear of the primary chamber and into the secondary chamber 